In the contemporary business environment, to adhere to the need of the customers, caused the shif... more In the contemporary business environment, to adhere to the need of the customers, caused the shift from mass production to mass-customization. This necessitates the supply chain (SC) to be effective flexible. The purpose of this paper is to seek flexibility through adoption of family-based dispatching rules under the influence of inventory system implemented at downstream echelons of an industrial supply chain network. We compared the family-based dispatching rules in existing literature under the purview of inventory system and information sharing within a supply chain network. The dispatching rules are compared for Average Flow Time performance, which is averaged over the three product families. The performance is measured using extensive discrete event simulation process. Given the various inventory related operational factors at downstream echelons, the present paper highlights the importance of strategically adopting appropriate family-based dispatching rule at the manufacturing end. In the environment of mass customization, it becomes imperative to adopt the family-based dispatching rule from the system wide SC perspective. This warrants the application of intra as well as inter-echelon information coordination. The holonic paradigm emerges in this research stream, amidst the holistic approach and the vital systemic approach. The present research shows its novelty in triplet. Firstly, it provides leverage to manager to strategically adopting a dispatching rule from the inventory system perspective. Secondly, the findings provide direction for the attenuation of adverse impact accruing from demand amplification (Bullwhip effect) in the form of inventory levels by appropriately adopting family-based dispatching rule. Thirdly, the information environment is conceptualized under the paradigm of Koestler's holonic theory.
International Journal of Physical Distribution & Logistics Management, 2006
PurposeThe primary objective of this paper is to show how mathematical modeling can be used for s... more PurposeThe primary objective of this paper is to show how mathematical modeling can be used for solving a third party logistics (3PL) allocation problem.Design/methodology/approachThe solution approach consists of finding a compromise solution for the six different strategies, defined in the paper by using lexicographic goal programming involving three objectives under some realistic constraints related to capacities of the markets.FindingsThis study investigates the usefulness and efficacy of the proposed method for a 3PL allocation problem for a case example of a typical fish supply network. The decision‐makers can evaluate the alternative solutions with respect to a set of decision criteria. The result indicates substantial improvement by reducing the number of 3PL service providers and reallocating them to the case fish markets.Practical implicationsThe work provides a useful decision model for practicing managers, policy makers and researchers of this area.Originality/valueThis...
Abstract: Application of Total Quality Management (TQM) approach has played an important role in ... more Abstract: Application of Total Quality Management (TQM) approach has played an important role in the survival and growth of many industries. Indian automobile sector has also adopted TQM path but it is still a player of little consequence in the global auto market. One of the major reasons for dismal performance of the Indian automobile sector can be attributed to the fact that it has not been able to prioritize and focus on the key variables, which are instrumental in enhancing TQM index. For the success of the Indian automobile ...
Several 1,5-diketones have been prepared in good to excellent yields by versatile conjugate addit... more Several 1,5-diketones have been prepared in good to excellent yields by versatile conjugate addition of nucleophiles such as cyclic or acyclic ketones, amines and thiols to a,b-unsaturated enones and alkynones, in the presence of catalytic amounts of 10% aq NaOH, TBAI and DMSO at ambient temperature. The choice of solvent and phase-transfer catalyst played a critical role in improving the reaction rate and yields of the products.
Journal of Polymer Science Part A: Polymer Chemistry, 2009
Terpolymers of acrylonitrile (A), methyl methacrylate (B), and methyl acrylate (M) were synthesiz... more Terpolymers of acrylonitrile (A), methyl methacrylate (B), and methyl acrylate (M) were synthesized under optimized atom transfer radical polymerization conditions using 2‐bromopropionitrile as an initiator and CuBr/dinonyl bipyridine as a catalyst. Variation of the feed composition led to terpolymers with different compositions. Composition of synthesized terpolymers were calculated from quantitative 13C{1H} NMR spectra. Number average molecular weight and polydispersity index were determined by gel permeation chromatography. The overlapping and broad signals of the terpolymers were assigned completely to various compositional and configurational sequences by correlation of one‐dimensional 1H, 13C{1H}, and distortionless enhancement by polarization transfer and two‐dimensional heteronuclear single quantum coherence (HSQC) and total correlation spectroscopy (TOCSY). 2D HSQC NMR study shows one to one correlation between carbon and proton signals, while 2D TOCSY spectra were used to ...
Isobornyl acrylate (B)/methacrylonitrile (N) copolymers with different compositions were synthesi... more Isobornyl acrylate (B)/methacrylonitrile (N) copolymers with different compositions were synthesized by the free‐radical bulk polymerization with azobisisobutyronitrile as the initiator under a nitrogen atmosphere at 70°C. The copolymer compositions were calculated from quantitative 13C(1H)NMR spectra. The reactivity ratios of the comonomers in the B/N copolymers determined from the linear Kelen–Tudos method and nonlinear error‐in‐variable method were rB = 0.66 ± 0.11 and rN = 1.54 ± 0.22 and rB = 0.74 and rN = 1.65, respectively. The complete spectral assignments of the 1H‐NMR and 13C(1H)‐NMR spectra were carried out with the help of distortionless enhancement by polarization transfer, two‐dimensional (2D) heteronuclear single quantum coherence, and 2D total correlation spectroscopy. The nitrile carbon of the N unit and the methine and OCH carbons of the B unit were assigned to triad compositional sequences, whereas the β‐methylene carbons of the B and N units were assigned to the ...
Despite total quality management (TQM) playing an important role in the survival and growth of th... more Despite total quality management (TQM) playing an important role in the survival and growth of the Indian automobile sector, India is still a player of little consequence in the global automobile production market. The paper identifies various dynamic interactions among the sub systems of TQM. The implications of these interactions have been captured using system dynamics modeling, which is based on causal relationship among different variables that constitute enablers and results. The model results have been discussed and validated based on a case study.
This research presents a novel approach to solve m-machine no-wait flow shop problem. A continuou... more This research presents a novel approach to solve m-machine no-wait flow shop problem. A continuous flow shop problem with total flow time as criterion is considered. This paper extends the artificial immune system (AIS) approach by proposing a new methodology termed as Psycho-Clonal algorithm. Proposed algorithm enjoys the flavor of AIS and Maslow's need hierarchy theory to evolve a meta heuristic. Numerical simulation with small and large number of jobs with respect to error percentage is reported. The results obtained are compared with the other existing approaches. Numerical simulation has revealed that results obtained using proposed algorithm have significant improvement over others.
Mechanical properties of any material are extensively influenced by the parameters such as strain... more Mechanical properties of any material are extensively influenced by the parameters such as strain, strain rate, temperature, and its composition. The characteristics of any material such as ductility, strain hardening, strength, dynamic recovery, grain growth, and recrystallization ...
Machine-loading problem of a flexible manufacturing system is known for its complexity. This prob... more Machine-loading problem of a flexible manufacturing system is known for its complexity. This problem encompasses various types of flexibility aspects pertaining to part selection and operation assignments along with constraints ranging from simple algebraic to potentially very complex conditional constraints. From the literature, it has been seen that simple genetic-algorithm-based heuristics for this problem lead to constraint violations and large number of generations. This paper extends the simple genetic algorithm and proposes a new methodology, constraint-based genetic algorithm (CBGA) to handle a complex variety of variables and constraints in a typical FMS-loading problem. To achieve this aim, three new genetic operators-constraint based: initialization, crossover, and mutation are introduced. The methodology developed here helps avoid getting trapped at local minima. The application of the algorithm is tested on standard data sets and its superiority is demonstrated. The solution approach is illustrated by a simple example and the robustness of the algorithm is tested on five well-known functions.
With the emergence of a business era that embraces ÔchangeÕ as one of its major characteristics, ... more With the emergence of a business era that embraces ÔchangeÕ as one of its major characteristics, manufacturing success and survival are becoming more and more difficult to ensure. The emphasis is on adaptability to changes in the business environment and on addressing market and customer needs proactively. Changes in the business environment due to varying needs of the customers lead to uncertainty in the decision parameters. Flexibility is needed in the supply chain to counter the uncertainty in the decision parameters. A supply chain adapts the changes if it is flexible and agile in nature. A framework is presented in this paper, which encapsulates the market sensitiveness, process integration, information driver and flexibility measures of supply chain performance. The paper explores the relationship among lead-time, cost, quality, and service level and the leanness and agility of a case supply chain in fast moving consumer goods business. The paper concludes with the justification of the framework, which analyses the effect of market winning criteria and market qualifying criteria on the three types of supply chains: lean, agile and leagile.
The cost and the time-to-market for a product will increase exponentially if innovations are not ... more The cost and the time-to-market for a product will increase exponentially if innovations are not brought and deployed into the product development cycle (PDC). This is due to the fact the system complexity is increasing exponentially with time. This increasing complexity results from introduction of new protocols, higher radio frequencies, and increasing number of applications, among others, in the case of mobile devices. Such factors have led to the exploration of the multi-core architecture. The software (SW) and hardware (HW) concurrency, and need for optimization, in such architectures, will further complicate the product development process. Therefore, it is imperative that we introduce new and innovative ways to enhance productivity. Researcher have proposed new concepts such as executable specifications, component based design, system modeling language (SysML), model driven design (MDD), software decomposition, abstract performance evaluation, system level verification, field programmable gate array (FPGA) based network-on-chip (NOC), and abstract concurrency modeling. These proposed modeling, design and development techniques aim at increasing productivity by introducing leading edge design methodologies into PDC. In this paper we present a cost model that aims at understanding the current PDC and at evaluating the impact of new technologies on PDC. We focus on cost and product development time, and compare them for the existing PDC and the new PDC that we have conceptualized. We refer to this new PDC as "One Pass to Production" (OPP). This cost model may also help one identify potential bottlenecks and areas for further automations.
International Journal of Health Care Quality Assurance, Nov 22, 2012
Purpose-The study is an attempt to highlight the value of the success rate performance of a surge... more Purpose-The study is an attempt to highlight the value of the success rate performance of a surgery while planning patient flow within a supply chain of a health care organization/hospital. Design/methodology/approach-We have considered one of the common surgeries, cataract, and the complications that subsequently results of this surgery. The study employs interpretive structural modeling (ISM) approach to draw a roadmap to study various complications causing cataract that subsequently help in planning and ...
The International Journal of Advanced Manufacturing Technology, 2014
The management of risks within the supply chain and external to it has become highly critical com... more The management of risks within the supply chain and external to it has become highly critical component of supply chain management. Inventory management is a vital tool to mitigate these risks. Lead times and review periods are important parameters in inventory management. The organizations focus on these parameters to enhance the system-wide supply chain performance in terms of services to customers. This paper aims at analyzing the efficiency of total supply chain in context of average fill rate performance. We analyze the efficiency of a hypothetical supply chain network structure which is subjected to time delays due to lead time and inventory review period changes. To understand the optimal relative efficiency among different values of average fill rate performance obtained through simulation, we used Data Envelopment Analysis approach (DEA). Taguchi experimental design procedure is used as a vehicle for conducting the simulation experiments and analyzing its outcome. The proposed integration of simulation with DEA framework provides practical implications to the decision maker as well as connotes to the real world situation where different enterprises compete for the frontier supply chain efficiency.
In the contemporary business environment, to adhere to the need of the customers, caused the shif... more In the contemporary business environment, to adhere to the need of the customers, caused the shift from mass production to mass-customization. This necessitates the supply chain (SC) to be effective flexible. The purpose of this paper is to seek flexibility through adoption of family-based dispatching rules under the influence of inventory system implemented at downstream echelons of an industrial supply chain network. We compared the family-based dispatching rules in existing literature under the purview of inventory system and information sharing within a supply chain network. The dispatching rules are compared for Average Flow Time performance, which is averaged over the three product families. The performance is measured using extensive discrete event simulation process. Given the various inventory related operational factors at downstream echelons, the present paper highlights the importance of strategically adopting appropriate family-based dispatching rule at the manufacturing end. In the environment of mass customization, it becomes imperative to adopt the family-based dispatching rule from the system wide SC perspective. This warrants the application of intra as well as inter-echelon information coordination. The holonic paradigm emerges in this research stream, amidst the holistic approach and the vital systemic approach. The present research shows its novelty in triplet. Firstly, it provides leverage to manager to strategically adopting a dispatching rule from the inventory system perspective. Secondly, the findings provide direction for the attenuation of adverse impact accruing from demand amplification (Bullwhip effect) in the form of inventory levels by appropriately adopting family-based dispatching rule. Thirdly, the information environment is conceptualized under the paradigm of Koestler's holonic theory.
International Journal of Physical Distribution & Logistics Management, 2006
PurposeThe primary objective of this paper is to show how mathematical modeling can be used for s... more PurposeThe primary objective of this paper is to show how mathematical modeling can be used for solving a third party logistics (3PL) allocation problem.Design/methodology/approachThe solution approach consists of finding a compromise solution for the six different strategies, defined in the paper by using lexicographic goal programming involving three objectives under some realistic constraints related to capacities of the markets.FindingsThis study investigates the usefulness and efficacy of the proposed method for a 3PL allocation problem for a case example of a typical fish supply network. The decision‐makers can evaluate the alternative solutions with respect to a set of decision criteria. The result indicates substantial improvement by reducing the number of 3PL service providers and reallocating them to the case fish markets.Practical implicationsThe work provides a useful decision model for practicing managers, policy makers and researchers of this area.Originality/valueThis...
Abstract: Application of Total Quality Management (TQM) approach has played an important role in ... more Abstract: Application of Total Quality Management (TQM) approach has played an important role in the survival and growth of many industries. Indian automobile sector has also adopted TQM path but it is still a player of little consequence in the global auto market. One of the major reasons for dismal performance of the Indian automobile sector can be attributed to the fact that it has not been able to prioritize and focus on the key variables, which are instrumental in enhancing TQM index. For the success of the Indian automobile ...
Several 1,5-diketones have been prepared in good to excellent yields by versatile conjugate addit... more Several 1,5-diketones have been prepared in good to excellent yields by versatile conjugate addition of nucleophiles such as cyclic or acyclic ketones, amines and thiols to a,b-unsaturated enones and alkynones, in the presence of catalytic amounts of 10% aq NaOH, TBAI and DMSO at ambient temperature. The choice of solvent and phase-transfer catalyst played a critical role in improving the reaction rate and yields of the products.
Journal of Polymer Science Part A: Polymer Chemistry, 2009
Terpolymers of acrylonitrile (A), methyl methacrylate (B), and methyl acrylate (M) were synthesiz... more Terpolymers of acrylonitrile (A), methyl methacrylate (B), and methyl acrylate (M) were synthesized under optimized atom transfer radical polymerization conditions using 2‐bromopropionitrile as an initiator and CuBr/dinonyl bipyridine as a catalyst. Variation of the feed composition led to terpolymers with different compositions. Composition of synthesized terpolymers were calculated from quantitative 13C{1H} NMR spectra. Number average molecular weight and polydispersity index were determined by gel permeation chromatography. The overlapping and broad signals of the terpolymers were assigned completely to various compositional and configurational sequences by correlation of one‐dimensional 1H, 13C{1H}, and distortionless enhancement by polarization transfer and two‐dimensional heteronuclear single quantum coherence (HSQC) and total correlation spectroscopy (TOCSY). 2D HSQC NMR study shows one to one correlation between carbon and proton signals, while 2D TOCSY spectra were used to ...
Isobornyl acrylate (B)/methacrylonitrile (N) copolymers with different compositions were synthesi... more Isobornyl acrylate (B)/methacrylonitrile (N) copolymers with different compositions were synthesized by the free‐radical bulk polymerization with azobisisobutyronitrile as the initiator under a nitrogen atmosphere at 70°C. The copolymer compositions were calculated from quantitative 13C(1H)NMR spectra. The reactivity ratios of the comonomers in the B/N copolymers determined from the linear Kelen–Tudos method and nonlinear error‐in‐variable method were rB = 0.66 ± 0.11 and rN = 1.54 ± 0.22 and rB = 0.74 and rN = 1.65, respectively. The complete spectral assignments of the 1H‐NMR and 13C(1H)‐NMR spectra were carried out with the help of distortionless enhancement by polarization transfer, two‐dimensional (2D) heteronuclear single quantum coherence, and 2D total correlation spectroscopy. The nitrile carbon of the N unit and the methine and OCH carbons of the B unit were assigned to triad compositional sequences, whereas the β‐methylene carbons of the B and N units were assigned to the ...
Despite total quality management (TQM) playing an important role in the survival and growth of th... more Despite total quality management (TQM) playing an important role in the survival and growth of the Indian automobile sector, India is still a player of little consequence in the global automobile production market. The paper identifies various dynamic interactions among the sub systems of TQM. The implications of these interactions have been captured using system dynamics modeling, which is based on causal relationship among different variables that constitute enablers and results. The model results have been discussed and validated based on a case study.
This research presents a novel approach to solve m-machine no-wait flow shop problem. A continuou... more This research presents a novel approach to solve m-machine no-wait flow shop problem. A continuous flow shop problem with total flow time as criterion is considered. This paper extends the artificial immune system (AIS) approach by proposing a new methodology termed as Psycho-Clonal algorithm. Proposed algorithm enjoys the flavor of AIS and Maslow's need hierarchy theory to evolve a meta heuristic. Numerical simulation with small and large number of jobs with respect to error percentage is reported. The results obtained are compared with the other existing approaches. Numerical simulation has revealed that results obtained using proposed algorithm have significant improvement over others.
Mechanical properties of any material are extensively influenced by the parameters such as strain... more Mechanical properties of any material are extensively influenced by the parameters such as strain, strain rate, temperature, and its composition. The characteristics of any material such as ductility, strain hardening, strength, dynamic recovery, grain growth, and recrystallization ...
Machine-loading problem of a flexible manufacturing system is known for its complexity. This prob... more Machine-loading problem of a flexible manufacturing system is known for its complexity. This problem encompasses various types of flexibility aspects pertaining to part selection and operation assignments along with constraints ranging from simple algebraic to potentially very complex conditional constraints. From the literature, it has been seen that simple genetic-algorithm-based heuristics for this problem lead to constraint violations and large number of generations. This paper extends the simple genetic algorithm and proposes a new methodology, constraint-based genetic algorithm (CBGA) to handle a complex variety of variables and constraints in a typical FMS-loading problem. To achieve this aim, three new genetic operators-constraint based: initialization, crossover, and mutation are introduced. The methodology developed here helps avoid getting trapped at local minima. The application of the algorithm is tested on standard data sets and its superiority is demonstrated. The solution approach is illustrated by a simple example and the robustness of the algorithm is tested on five well-known functions.
With the emergence of a business era that embraces ÔchangeÕ as one of its major characteristics, ... more With the emergence of a business era that embraces ÔchangeÕ as one of its major characteristics, manufacturing success and survival are becoming more and more difficult to ensure. The emphasis is on adaptability to changes in the business environment and on addressing market and customer needs proactively. Changes in the business environment due to varying needs of the customers lead to uncertainty in the decision parameters. Flexibility is needed in the supply chain to counter the uncertainty in the decision parameters. A supply chain adapts the changes if it is flexible and agile in nature. A framework is presented in this paper, which encapsulates the market sensitiveness, process integration, information driver and flexibility measures of supply chain performance. The paper explores the relationship among lead-time, cost, quality, and service level and the leanness and agility of a case supply chain in fast moving consumer goods business. The paper concludes with the justification of the framework, which analyses the effect of market winning criteria and market qualifying criteria on the three types of supply chains: lean, agile and leagile.
The cost and the time-to-market for a product will increase exponentially if innovations are not ... more The cost and the time-to-market for a product will increase exponentially if innovations are not brought and deployed into the product development cycle (PDC). This is due to the fact the system complexity is increasing exponentially with time. This increasing complexity results from introduction of new protocols, higher radio frequencies, and increasing number of applications, among others, in the case of mobile devices. Such factors have led to the exploration of the multi-core architecture. The software (SW) and hardware (HW) concurrency, and need for optimization, in such architectures, will further complicate the product development process. Therefore, it is imperative that we introduce new and innovative ways to enhance productivity. Researcher have proposed new concepts such as executable specifications, component based design, system modeling language (SysML), model driven design (MDD), software decomposition, abstract performance evaluation, system level verification, field programmable gate array (FPGA) based network-on-chip (NOC), and abstract concurrency modeling. These proposed modeling, design and development techniques aim at increasing productivity by introducing leading edge design methodologies into PDC. In this paper we present a cost model that aims at understanding the current PDC and at evaluating the impact of new technologies on PDC. We focus on cost and product development time, and compare them for the existing PDC and the new PDC that we have conceptualized. We refer to this new PDC as "One Pass to Production" (OPP). This cost model may also help one identify potential bottlenecks and areas for further automations.
International Journal of Health Care Quality Assurance, Nov 22, 2012
Purpose-The study is an attempt to highlight the value of the success rate performance of a surge... more Purpose-The study is an attempt to highlight the value of the success rate performance of a surgery while planning patient flow within a supply chain of a health care organization/hospital. Design/methodology/approach-We have considered one of the common surgeries, cataract, and the complications that subsequently results of this surgery. The study employs interpretive structural modeling (ISM) approach to draw a roadmap to study various complications causing cataract that subsequently help in planning and ...
The International Journal of Advanced Manufacturing Technology, 2014
The management of risks within the supply chain and external to it has become highly critical com... more The management of risks within the supply chain and external to it has become highly critical component of supply chain management. Inventory management is a vital tool to mitigate these risks. Lead times and review periods are important parameters in inventory management. The organizations focus on these parameters to enhance the system-wide supply chain performance in terms of services to customers. This paper aims at analyzing the efficiency of total supply chain in context of average fill rate performance. We analyze the efficiency of a hypothetical supply chain network structure which is subjected to time delays due to lead time and inventory review period changes. To understand the optimal relative efficiency among different values of average fill rate performance obtained through simulation, we used Data Envelopment Analysis approach (DEA). Taguchi experimental design procedure is used as a vehicle for conducting the simulation experiments and analyzing its outcome. The proposed integration of simulation with DEA framework provides practical implications to the decision maker as well as connotes to the real world situation where different enterprises compete for the frontier supply chain efficiency.
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Papers by Ravi Shankar